Electrical circuit assemblies are known to comprise at least two electrical circuits and means for interconnecting a primary one of the circuits to the other circuits. Such circuit assemblies are commonly used as circuit test fixtures to functionally test the performance of the primary circuit. In this case, the other circuits are used to provide direct current (DC) power to the circuit under test and to support data acquisition during the functional testing. For example, an electrical circuit assembly is typically used to test the performance of radio frequency (RF) power amplifiers prior to their insertion into two-way radio products, such as base stations, mobile radios, and portable radios. To enable the RF amplifiers to be tested, an external DC power supply is typically coupled to the amplifier via one type of interconnect mechanism, while an RF source and load are connected to the amplifier via another type of interconnect mechanism. It is also known that the DC and RF interconnect mechanisms may be substantially identical.
To prevent damage to the primary circuit during the functional testing, solderess interconnect mechanisms are commonly used to connect the DC and support circuits to the circuit under test. In a typical RF application, DC power is supplied to an RF amplifier circuit through spring-loaded metallic pins, and the RF source and load are connected to the amplifier through spring-loaded RF connectors, such as SMA-style connectors. The RF connectors and DC pins are typically attached to a non-conductive supporting structure, such as a machined plastic plate. Prior to testing the amplifier, the supporting structure is automatically positioned upon the RF amplifier circuit such that the springs in the spring-loaded pins and connectors are compressed to provide electrical connection between the RF amplifier and the DC power and RF support circuits.
Although this approach provides solderless connections between the RF amplifier and the other necessary testing circuitry, the interconnections become unreliable over time due to spring fatigue, such as stress relaxation or cracking, that results from multiple compression and expansion cycles. Thus, to insure reliable interconnections, the springs require periodic maintenance, which results in undesired increases in product test cycle times. Further, in high frequency RF applications, the spring-loaded DC pins negatively impact the functional performance of the RF amplifier circuit since they approximate small antennas and, accordingly, disturb the electromagnetic fields resident in the RF circuit.
Another approach commonly employed in RF circuit assemblies is to use manually actuated fasteners to provide the solderless connection between the circuit under test and the requisite supporting circuitry. Unlike their spring-loaded counterparts, the manually actuated fasteners are located about the periphery of the RF test circuit and, when actuated, provide the necessary contact force to produce electrical connectivity between the RF test circuit and the supporting circuitry. Although the manually actuated fasteners overcome the deficiencies of the spring-loaded interconnect mechanisms, they require and rely on human actuation. Thus, if a manually actuated fastener is inadvertently not engaged and, accordingly, creates an open circuit during the functional testing, damage to the circuit under test may result.
Therefore, a need exists for an electrical circuit assembly that facilitates automatic control of a solderless, electrical connection between two circuits, while maintaining reliability of the electrical connection and being substantially maintenance free.